In general, encapsidated viruses include a protein coat or “capsid” that is assembled to contain the viral nucleic acid. Many viruses have capsids that can be “self-assembled” from the individually expressed capsids, both within the cell the capsid is expressed in (“in vivo assembly”) forming VLPs, and outside of the cell after isolation and purification (“in vitro assembly”). Ideally, capsids are modified to contain a target recombinant peptide, generating a recombinant viral capsid-peptide fusion. The fusion peptide can then be expressed in a cell, and, ideally, assembled in vivo to form recombinant viral or virus-like particles.
This approach has been met with varying success. See, for example, C Marusic et al., J. Virol. 75 (18):8434-39 (September 2001) (expression in plants of recombinant, helical potato virus X capsids terminally fused to an antigenic, HIV peptide, with in vivo formation of recombinant virus particles); F R Brennan et al., Vaccine 17 (15-16):1846-57 (9 Apr. 1999) (expression in plants of recombinant, icosahedral cowpea mosaic virus or helical potato virus X capsids terminally fused to an antigenic, Staphylococcus aureus peptide, with in vivo formation of recombinant virus particles).
U.S. Pat. No. 5,874,087 to Lomonossoff & Johnson describes production of recombinant plant viruses, in plant cells, where the viral capsids include capsids engineered to contain a biologically active peptide, such as a hormone, growth factor, or antigenic peptide. A virus selected from the genera Comovirus, Tombusvirus, Sobemovirus, and Nepovirus is engineered to contain the exogenous peptide encoding sequence and the entire engineered genome of the virus is expressed to produce the recombinant virus. The exogenous peptide-encoding sequence is inserted within one or more of the capsid surface loop motif-encoding sequences.
Attempts have been made to utilize non-tropic cells to produce particular virus like particles. See, for example, J W Lamb et al., J. Gen. Virol. 77 (Pt. 7):1349-58 (July 1996), describing expression in insect cells of recombinant, icosahedral potato leaf roll virus capsids terminally fused to a heptadecapeptide, with in vivo formation of virus-like particles. In certain situations, a non-tropic VLP may be preferable. For instance, a non-tropic viral capsid may be more accommodating to foreign peptide insertion without disrupting the ability to assemble into virus like particles than a native viral capsid. Alternatively, the non-tropic viral capsid may be better characterized and understood than a capsid from a native, tropic virus. In addition, the particular application, such as vaccine production, may not allow for the use of a tropic virus in a particular host cell expression system. U.S. Pat. No. 6,232,099 to Chapman et al. describes the use of rod-shaped viruses to produce foreign proteins connected to viral capsid subunits in plants. Rod-shaped viruses, also classified as helical viruses, such as potato virus X (PVX) have recombinant peptides of interest inserted into the genome of the virus to create recombinant viral capsid-peptide fusions. The recombinant virus is then used to infect a host cell, and the virus actively replicates in the host cell and further infects other cells. Ultimately, the recombinant viral capsid-peptide fusion is purified from the plant host cells.
Meanwhile, there are many kinds of catalysts, such as a metal, a metal oxide, a solid acid, and the like. In addition, a producing method can largely be classified into an infiltration method (after immersing a support into a solution dissolving an active material, the active material is supported at the support by evaporating or adding a precipitate), an ion exchange method (an active material is exchanged to a support by contacting the support with the solution dissolving the active material), a precipitation method (passing through a activating process by precipitating the active material in a solution state), and the like. Of these, the present invention, which is a specific method out of the infiltration method of metal catalyst, uses a metal nickel as a catalyst because a nickel oxide (NiO) does not have an activity as a catalyst. In addition, since the nickel is easily made in desired shapes and desired sizes by using a nanotemplate as compared with the nickel oxide, it is often used to study a catalytic action of a metal wire, a metal thin film, a metal crystal, and the like by using the nickel. For example, a nickel nanohair structure is able to be biofunctionalized for the application in the field of biotechnology (BT). Especially, the exposed part of nickel nanowire can be used in a biosensor using the affinity of biomolecules-probe, antibody-antigen and biotin-avidin through a surface modification. Especially, the applicability of nickel nanowire can be greatly improved because the nickel can selectively bind with amine and histidine. In addition, it can also be possible to control the movement of nanostructure by using a magnetic property of nickel. However, it is extremely difficult to get the individual property from the AAO-free nanowire because an agglomeration phenomenon is generated due to a magnetic property and van der Waals forces.
Here, the nickel nanohair structure according to the present invention is a very useful nanomaterial for the chemical detection because it is uniform in height; the agglomeration phenomenon is prevented by being inside the nanotemplate; and it has a high density. Therefore, synthesizing method of a nanostructure is required for the study of the nickel nanohair structure.
Furthermore, the fabrication of nanostructures on transparent materials, such as quartz and glass, is under active investigation in a range of applications of sensor systems (P. Skladal, Chem. Soc. 2003, 14, 491; Z. Liu, M. D. Amiridis, J. Phys. Chem. B 2005, 109, 16866). In particular, quartz structures have been employed in various optical and optoelectrical applications on account of their good electrical insulation, absence of electromagnetic interference from other electric devices, excellent transparency for UV to visible light, good chemical stability, and high mechanical strength (A. Gopinath, S. V. Boriskina, N.-N. Feng, B. M. Reinhard, L. D. Negro, Nano Lett. 2008, 8, 2423; A. Dmitriev, C. Hagglund, S. Chen, H. Fredriksson, T. Pakizeh, M. Kall, D. S. Sutherland, Nano Lett. 2008, 8, 3893; T. Lohmuller, M. Helgert, M. Sundermann, R. Brunner, J. P. Spatz, Nano Lett. 2008, 8, 1429.).
In recent decades, plasma-related technologies have been employed for surface processing of various materials and for the production of nanostructured materials in both research and industrial settings.
Surface processing using plasma-related technologies can be categorized into two types: 1) surface modification, which results in a change in the chemical composition of a surface; and 2) selective dry-etching using reactive ionic species produced by a plasma, which makes it possible to fabricate nanometer-scale patterns on high-end materials. The latter technology, i.e., reactive ion etching (RIE), has been intensively employed in silicon-based technologies. Although masks are generally used to fabricate nanometer-scale patterns, RIE has been applied without a mask to fabricate micro- and nanostructures in some studies. However they utilized an undesirable artifact of etching, known as “RIE grass,” that prevents clean delayering of integrated circuits (H. G. Craighead, R. E. Howard, J. E. Sweeney, D. M. Tennant, J. Vac. Sci. Technol. 1982, 20, 316; M. Gotza, B. Saint-Cricq, M. Dutoit, P. Jouneau, Microelectron. Eng. 1995, 27, 129; M. Gharghi, S. J. Sivoththaman, Vac. Sci. Technol. 2006, 24, 723; W. E. Vanderlinde, C. J. V. Benken, A. R. Crockett, Proc. Soc. Photo. Opt. Instrum. Eng. 1996, 2874).
RIE grass occurs as the result of the re-deposition of cathode materials (typically aluminum) or of polymerized complexes, such as fluorinated carbon onto the silicon or silicon oxide surface (M. Gharghi, S. J. Sivoththaman, Vac. Sci. Technol. 2006, 24, 723). With RIE grass formation alone, it is difficult to control the spacing of nanostructures, and therefore, there is a significant need for a new method to efficiently space nanostructures while avoiding the RIE grass formation.
The application of the etched quartz plates to biosensor systems that are subjected to detecting protein analytes requires immobilization of probe antibodies on the surface of nanostructured quartz plates, which is a key step to determine the sensitivity. The previous immobilization methods are based on direct antibody-surface binding that is performed using one of the following principles: 1) physical adsorption by hydrophobic interaction; 2) covalent linking between antibodies and a chemically activated solid surface; and 3) molecular affinity interactions, including specific binding of biotinylated antibodies to surface avidin (F. Rusmini, Z. Zhong, J. Feijen, Biomacromol. 2007, 8, 1775; W. Kusnezow, J. D. Hoheisel, J. Mol. Recognit. 2003, 16, 165; Y. Jung, Y. Jeong, B. H. Chung, Analyst 2008, 133, 697). Physical adsorption methods cause random/uncontrolled orientation of immobilized antibodies due to nonspecific binding of antibodies to the surface. Denaturation of antigen-binding domains (active sites) of antibodies may occur during the covalent linking of antibodies to chemically modified surfaces (F. Rusmini, Z. Zhong, J. Feijen, Biomacromol. 2007, 8, 1775; W. Kusnezow, J. D. Hoheisel, J. Mol. Recognit. 2003, 16, 165). Also, site-specific biotinylation of antibodies is almost impossible; that is, biotin may attach to any lysine residue(s) close to active sites of antibody and thereby interfere with the binding of target antigens to the active sites, and the random/uncontrolled orientation problems of antibodies still remains unsolved. These undesirable problems significantly reduce the sensitivity and specificity of biosensors (Y. Jung, Y. Jeong, B. H. Chung, Analyst 2008, 133, 697).
A plausible method to solve these problems is to use an antibody binding protein, such as bacterial Protein A or Protein G, which binds only to Fc domain of antibody. The approach does not require additional steps to chemically modify probe antibodies and therefore, can maintain intact active site of antibodies, allowing efficient and specific binding of antigens.
For an embodiment of the present invention, the present inventors propose the use of genetically engineered Hepatitis B virus (HBV) capsid particles that expose both biotinylated peptides and Staphylococcal Protein A in order to densely immobilize probe antibodies with well-organized orientation on nanostructured quartz.
Meanwhile, an early detection [Adams, J. E. et al. Circulation 88, 101-106 (1993); Adams, J. E., Schechtman, K. B., Landt, Y., Ladenson, J. H. & Jaffe, A. S. Clin. Chem. 40, 1291-1295 (1994); Thygesen, K., Alpert, J. S. & White, H. D. J. Am. Coll. Cardiol. 50, 2173-2195 (2007); Morrow, D. A. et al. Clin. Chem. 53, 552-574 (2007); Gibler, W. B. et al. Ann. Emerg. Med. 46, 185-197 (2005)] of Troponin I (Protein Marker) from a patient suffered with high risk acute myocardial infarction can reduce a risk rate of deaths from heart attack [Antman, E. M. et al. N. Engl. J. Med. 335, 1342-1349 (1996); Wu, A. H. B. & Jaffe, A. S. Am. Heart J. 155, 208-214 (2008); Benamer, H. et al. Am. Heart J. 137, 815-820 (1999); Heeschen, C., van den Brand, M. J., Hamm, C. W. & Simoons, M. L. Circulation 100, 1509-1514 (1999); Wong, G. C. et al. Circulation 106, 202-207 (2002)].
Most Troponin assays are currently based on the conventional Enzyme Linked Immunosorbent Assay (ELISA) and have detection limits in the nano- and picomolar range [Rosi, N. L. & Mirkin, C. A. Chem. Rev. 105, 1547-1562 (2005)].
The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.